This invention relates to spiral mascara brushes. As contemplated herein, a spiral mascara brush comprises a multiplicity of bristles each having opposed free ends, and means for fixedly mounting the bristles in a continuous spiral array such that the free ends of the bristles are disposed along a helix. Typically, the mounting means is an initially U-shaped wire, which is twisted into a tight, axially rectilinear helix (after the bristles have been positioned between the legs of the U) to grip the bristles firmly at their midsections and to spread them into the aforementioned spiral array. The bristle array, which may, for example, be cylindrical (having bristles of uniform length from base to tip of the brush) or conical (having bristles of progressively shorter length toward the brush tip), is dimensioned to be inserted within a mascara container, for immersion of the bristles in the contained mascara. The wire or other mounting means projects beyond the base of the bristle array and is commonly embedded in a plastic shank projecting axially from the interior of a mascara container cap, so that when the cap is mounted in closed position on a container, the brush is disposed inside the container with the bristles immersed as aforesaid. Brushes of this type are well known and widely used at the present day.
The conventional purpose of a spiral mascara brush is to apply mascara to a user's eyelashes, i.e. to pick up and transport mascara from the mascara container and to deposit the transported mascara on the eyelashes. For this purpose, the bristles must be soft (relatively low in flexural strength), because stiff bristles do not satisfactorily pick up, transport, and deposit mascara. An illustrative example of a bristle suitable for applying mascara is a nylon 6.12 fiber commercially available from E.I. dePont de Nemours & Co. under the trade name "TYNEX", having a diameter of 0.003 inch .+-.0.0005 inch .+-.15%.
Owing to its high viscosity, mascara, as applied to eyelashes, tends to deposit unevenly in the form of clumps. To achieve desired uniformity of distribution on the eyelashes, the applied mascara must be combed through the lashes. Mascara brush bristles soft enough to apply mascara, however, are too soft to comb eyelashes; when pressed against the lashes, they simply flex and do not penetrate the lashes as required to effect combing.
Accordingly, separate implements (e.g., toothed combs) have heretofore sometimes been provided for performing the combing function. The provision of two separate implements for applying and distributing or combing mascara is disadvantageous from the standpoint of cost and convenience to the user. Moreover, while a mascara-applying brush is protected (when not in use) by insertion in the closed mascara container, the second (combing) implement is not thus protected and may be exposed to contamination which can cause infections.